The invention relates to a subunit of a throttle valve housing. Throttle valve housings are known. DE 195 12 874 A1 and also FR 2 687 601 A1 describe a throttle valve housing which is arranged in a tubular casing. Here, the throttle valve is fastened on a throttle valve shaft which is mounted so as to rotate in bearings and to pass through recesses in the casing wall at its free ends transversely with respect to the longitudinal axis of the tubular casing. In the closed state, the throttle valve divides the casing into a suction side and into a side in which atmospheric pressure prevails. In this known throttle valve housing, it is disadvantageous that, as a result of the vacuum which is present in the suction side, leakage air can pass via the bearings of the throttle valve shaft into the suction side, which is not desirable.
US 2003/0034474 A1 describes a throttle valve which is arranged in an inclined manner with respect to the throttle valve shaft. Additional measures are not described for sealing between the circumferential edge of the throttle valve and the throttle valve housing. U.S. Pat. No. 3,260,502 and U.S. Pat. No. 4,899,984 describe throttle valves made from metal, in which circumferential sealing elements are provided. In order to seal these sealing elements against the inner side of the throttle valve housing, additional elastic elements are provided which press the sealing ring against the throttle valve housing on one side and against the throttle valve on the other side.
The invention is therefore based on the object of providing a subunit for a throttle valve housing, as a result of which subunit it is largely avoided that leakage air flows in via the bearings of the throttle valve shaft to the suction side of the air duct.